Stretch film, also known as stretch film and heat shrink film, is the first in China to produce PVC stretch film with PVC as base material and DOA as plasticizer and self-adhesive effect. Due to environmental protection issues, high cost (relative to PE's high proportion, less unit packaging area), poor stretch-ability, etc., it was gradually eliminated when the domestic production of PE stretch film was started from 1994 to 1995. The PE stretch film first uses EVA as the self-adhesive material, but its cost is high and it has a taste. Later, PIB and VLDPE are used as self-adhesive materials, and the base material is mainly LLDPE. Stretch film can be divided into: PE stretch film, PE stretch stretch film, LLDPE stretch stretch film, PE slit stretch film, etc.